Analysis of the sample preparation methods based on piecewise variation coefficients of component mass fractions

2021 ◽  
pp. 15-19
Author(s):  
V. Z. Kozin ◽  
A. S. Komlev ◽  
E. V. Stupakova
Keyword(s):  
Sample Preparation ◽  
Relative Error ◽  
Preparation Method ◽  
Sampling Error ◽  
Theoretical Description ◽  
Random Errors ◽  
Copper Ore ◽  
Preparation Methods ◽  
Mass Fractions ◽  
Sample Preparation Methods

Sample preparation methods are usually developed following respective recommendations of the applicable sampling standards. Modern sampling theories allow designing and optimizing these methods. Random errors in sample preparation are calculated based on a theoretical description of the piecewise heterogeneity of the sample obtained using the formulas for the fundamental sampling error. The concept of a piecewise coefficient of variation is introduced and used to develop a formula for the relative error of the sample preparation method. Using a method compiled in accordance with GOST 14180-80 for copper ore as an example, the relative error is established for the preparation of an ore sample with the copper mass fraction of 1.3 %. It is shown that a change in the final preparation size from 0.1 to 0.08 mm affects the error only insignificantly, and sample size changes by stages allow designing a preparation method with the smallest error. It is advisable to analyze the method compiled and change its parameters on the basis of a structural assessment of the influence of individual preparation stages on the error. Sample preparation examples for copper and gold-bearing ore are used to demonstrate the analysis procedure and the parameter changes. Traditionally, the minimum sample masses are established for all stages based on the volumetric heterogeneity of the sample being tested and the size of the sample material. The minimum masses should be found depending on the grain size of the valuable mineral in the ore, the permissible relative error for the size reduction, and the material size for the sample reduced by a factor of 1.5 for nonferrous metal ores.

Study on Sample Preparation Method of DEM

2013 ◽  
Vol 671-674 ◽  
pp. 333-336
Author(s):  
Yang Liu ◽  
Xian De Zhu ◽  
Chen Ye Wan
Keyword(s):  
Sample Preparation ◽  
Discrete Element Method ◽  
Preparation Method ◽  
Descent Method ◽  
Mechanical Parameters ◽  
Sample Preparation Method ◽  
Preparation Methods ◽  
Dem Model ◽  
Compaction Method ◽  
Sample Preparation Methods

Three numerical sample preparation methods, namely, radius expand method, hierarchical compaction method and gravity descent method, were studied using discrete element method (DEM) to simulate the actual sample. The processes of these three methods were described in details and the differences of these three methods were discussed. The impacts of mechanical parameters in DEM model on the numerical results were analyzed.

Validation of Solus One Salmonella from Select Food Matrixes and Stainless-Steel and Plastic Environmental Surfaces

2019 ◽  
Vol 102 (4) ◽  
pp. 1145-1161
Author(s):  
David Higgins ◽  
Holly Urquhart ◽  
Siobhan Kelly ◽  
Simon Illingworth ◽  
Nevin Perera ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Sample Preparation ◽  
Preparation Method ◽  
Comparison Study ◽  
Sample Preparation Method ◽  
Preparation Methods ◽  
Environmental Surfaces ◽  
Automated Sample Preparation ◽  
The U.S ◽  
Sample Preparation Methods

Abstract Background: Solus One Salmonella is designed to accurately detect Salmonella species (Salmonella enterica subspecies enterica, salamae, arizonae, diarizonae, houtenae, indica, and Salmonella bongori) from select food matrixes and stainless-steel and plastic environmental surfaces. Solus One Salmonella uses an antibody-based technology test system that is paired with media and our proprietary media supplement, the Solus One Salmonella supplement combined with a manual or automated sample preparation method. Objective: Solus One Salmonella was evaluated for inclusivity and exclusivity, and a matrix comparison study was done for six food matrixes (raw beef trim, pasteurized liquid egg, raw salmon, cheddar cheese, Romaine lettuce, nonfat dry milk) and two environmental surfaces (stainless steel and polystyrene). Methods: Solus One Salmonella was compared with the U.S. Food and Drug Administration Bacteriological Analytical Manual Chapter 5: Salmonella (July 2018) and the U.S. Department of Agriculture Food Safety and Inspection Service Microbiology Laboratory Manual, 4.09 (January 2017) in the matrix study. Both the manual and automated sample preparation methods were performed for cheddar cheese and stainless-steel environmental surfaces. Results: For the inclusivity and exclusivity evaluation, Solus One Salmonella correctly detected all 108 target organism isolates and correctly excluded all 35 nontarget strains that were analyzed. Conclusions: In the method comparison study, both Solus One Salmonella manual and automated sample preparation methods demonstrated no significant differences based on probability of detection (POD) statistical analysis between presumptive and confirmed results or between candidate and reference method results for the six food matrixes after 20–22 h and two environmental surfaces after 16–20 h of enrichment time. POD analysis of Solus One Salmonella method robustness, product consistency, and stability studies using the automated sample preparation method demonstrated no statistically significant differences.

scholarly journals Sample Preparation Methods Affect Engineering Characteristic Tests of Municipal Solid Waste

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Dequan Kong ◽  
Rong Wan ◽  
Yonghui Wang
Keyword(s):  
Sample Preparation ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
Preparation Method ◽  
Engineering Properties ◽  
Direct Shear ◽  
Compression Tests ◽  
Preparation Methods ◽  
Engineering Parameters ◽  
Sample Preparation Methods

The output of municipal solid waste (MSW) has sharply increased over the recent years, which induces many severe problems (environmental pollution, deteriorating human health, and increased land occupation). Engineering parameters form the research basis for MSW treatment, which can be greatly influenced by the applied sample preparation methods. Currently, the preparation method of MSW samples mostly refers to the geotechnical test standard. The suitability and accuracy of this method for MSW are less studied, especially when considering biodegradation, so further research is needed. Depending on whether the material is dried or remains wet during preparation, the samples made by traditional geotechnical test standards are referred to as dry method samples or wet method samples, respectively. To study the influence of the sample preparation methods on the MSW engineering properties of MSW, the compression tests, direct shear tests, and biodegradation compression tests were conducted for both types of samples (dry and wet). The results show that the data dispersion of the wet method samples is stronger. The average test data variance of wet samples was 1.43–8.85 times higher than that of dry samples. In both the direct shear test and the compression test, the differences in engineering parameters caused by the sample preparation method were less than 12.3% and 8.9%, respectively. In biodegradation compression tests, the difference in engineering parameters reached up to 33.7%. In general, the dry method is preferred for tests that do not consider biodegradation, while the wet method is more suitable for tests that consider biodegradation. The research can be used as a reference toward improving the simplicity and accuracy of MSW tests.

scholarly journals Validation of Sample Preparation Methods for Microplastic Analysis in Wastewater Matrices—Reproducibility and Standardization

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2445 ◽  
Author(s):  
Mohammed S. M. Al-Azzawi ◽  
Simone Kefer ◽  
Jana Weißer ◽  
Julia Reichel ◽  
Christoph Schwaller ◽  
...  
Keyword(s):  
Organic Matter ◽  
Sample Preparation ◽  
Natural Organic Matter ◽  
Preparation Method ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Preparation Methods ◽  
Wastewater Samples ◽  
Key Aspects ◽  
Sample Preparation Methods

There is a growing interest in monitoring microplastics in the environment, corresponding to increased public concerns regarding their potential adverse effects on ecosystems. Monitoring microplastics in the environment is difficult due to the complex matrices that can prevent reliable analysis if samples are not properly prepared first. Unfortunately, sample preparation methods are not yet standardized, and the various efforts to validate them overlook key aspects. The goal of this study was to develop a sample preparation method for wastewater samples, which removes natural organic matter without altering the properties of microplastics. Three protocols, based on KOH, H2O2, and Fenton reactions, were chosen out of ten protocols after a literature review and pre-experiments. In order to investigate the effects of these reagents on seven polymers (PS, PE, PET, PP, PA, PVC, and PLA), this study employed µFTIR, laser diffraction-based particle size analysis, as well as TD-Pyr-GC/MS. Furthermore, the study discussed issues and inconsistencies with the Fenton reactions reported in the literature in previous validation efforts. The findings of this study suggest that both H2O2 and Fenton reactions are most effective in terms of organic matter removal from microplastic samples while not affecting the tested polymers, whereas KOH dissolved most PLA and PET particles.

Improving Sample Preparation Methods For Cannabis-Infused Edible And Topical Products

Planta Medica ◽  
2016 ◽  
Vol 82 (05) ◽  
Author(s):  
M Wilcox ◽  
M Jacyno ◽  
J Marcu ◽  
J Neal-Kababick
Keyword(s):  
Sample Preparation ◽  
Preparation Methods ◽  
Sample Preparation Methods

Thin-Die Flip Chip Physical-FA Process Flow

2002 ◽  
Author(s):  
Andrew J. Komrowski ◽  
N. S. Somcio ◽  
Daniel J. D. Sullivan ◽  
Charles R. Silvis ◽  
Luis Curiel ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Failure Analysis ◽  
Flip Chip ◽  
Semiconductor Industry ◽  
Organic Substrate ◽  
Fault Isolation ◽  
Preparation Methods ◽  
Chip Technology ◽  
Isolation Test ◽  
Sample Preparation Methods

Abstract The use of flip chip technology inside component packaging, so called flip chip in package (FCIP), is an increasingly common package type in the semiconductor industry because of high pin-counts, performance and reliability. Sample preparation methods and flows which enable physical failure analysis (PFA) of FCIP are thus in demand to characterize defects in die with these package types. As interconnect metallization schemes become more dense and complex, access to the backside silicon of a functional device also becomes important for fault isolation test purposes. To address these requirements, a detailed PFA flow is described which chronicles the sample preparation methods necessary to isolate a physical defect in the die of an organic-substrate FCIP.

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